1. Field of the Invention
The present invention relates to trailing arm type suspension systems for vehicles.
2. Background Art
Vehicle suspension systems generally include a plurality of links between the frame of the vehicle and a wheel support knuckle. The wheel support knuckle is connected to the frame of the vehicle by upper and lower control arms, or links, that form an articulated linkage. The linkage allows the vehicle to move relative to the wheel in a controlled manner. Shock absorbers and springs are provided to absorb impacts and provide a smooth ride. Other links that connect the wheel support knuckle to the vehicle include camber links and toe links that provide for adjustment of the wheel position.
Suspension systems are designed to provide the desired ride and handling characteristics for a particular vehicle. For example, sports cars are generally provided with tight suspensions to improve handling. On the other hand, luxury cars are provided with suspensions that are tuned to provide a softer ride with somewhat reduced handling performance.
Traditional trailing arm designs having a cast knuckle generally require the toe link to be secured to the cast knuckle. Complex knuckle assemblies are relatively expensive to produce and increase the weight of the entire suspension system. Each bearing, or receptacle, incorporated in a wheel support knuckle increases the complexity and cost to manufacture the vehicle suspension system because more machining is required.
In some suspension systems, it may be advantageous to provide an integrated caliper track to which a disk brake caliper may be mounted on a cast knuckle. Providing a cast knuckle with brake and hub/rotor receptacles is an advantage that is not readily achieved by prior art stamped trailing arm and wheel support knuckle designs.
There is a need for a method of making a hybrid stamped and cast trailing arm and wheel support knuckle for vehicle suspension systems that reduces system weight and cost. Any such solution must be durable and should be sufficiently robust to withstand stresses encountered by SUV or off-road vehicles. In addition, there is a need for a hybrid trailing arm/wheel support knuckle that can accommodate an integrated caliper for vehicle brake systems.
These and other problems and needs are addressed by Applicants' invention as summarized below.